Swirling in and out in flood (10)

I believe the answer is:

inundation

'flood' is the definition.
(I know that flood can be written as inundation)

'swirling in and out in' is the wordplay.
'swirling' indicates an anagram.
'in'+'and'+'out'+'in'='inandoutin'
'inandoutin' with letters rearranged gives 'INUNDATION'.

(Another definition for inundation that I've seen is " Flood".)

I've seen this clue in The Telegraph.

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